A machine, such as an electric motor (e.g., a totally-enclosed fan-cooled motor), typically does not allow outside air to freely circulate through an interior of the motor. An external fan or blower is often attached to one end of the motor and the air is blown over the body surface or fins of the motor to cool it.
Using convention cooling methods, the heat generated, for example, due to losses in the motor during operation, are generally kept within allowable limits. However, these conventional cooling methods suffer from temperature gradients from a fan end to another end (e.g., exit end) which restricts the operation of the motor and the maximum achievable rating.